Aldosterone is a mineralocorticoid hormone synthesized at the adrenal cortex, and can bind to the mineralocorticoid receptor and activate the receptor to promote the conservation of sodium and the excretion of potassium. It may have an important role in keeping the electrolyte balance and changing the structure and function of endothelial cells, vascular smooth muscle cells and fibroblasts on the arterial wall as well as the arterial adventitia and the matrix on its media. The high level of aldosterone may result in the abnormal activation of the mineralocorticoid receptor, which can cause the electrolyte imbalance, the blood vessel injury, the fibrosis and the like, and result in the cardiovascular disease such as hypertension, the injury to the organ such as kidney, heart and brain, the endocrine disturbance and the like. A drug that blocks the binding of aldosterone and the mineralocorticoid receptor by competitively binding to the mineralocorticoid receptor can therefore inhibit the aldosterone-mediated injury and reduce the occurrence of the above mentioned disease.
The compound represented by Formula (1), 2-chloro-4-[(3S,3aR)-3-cyclopentyl-7-(4-hydroxypiperidin-1-carbonyl)-3,3a,4,5-tetrahydro-2H-pyrazolo[3,4-f]quinolin-2-yl]benzonitrile, as disclosed in the application WO2012022121, is an aldosterone receptor antagonist, which can selectively bind to the mineralocorticoid receptor, and has a lower affinity to the glucocorticoid and the androgen receptor.

WO2012022121 discloses a process for preparing the compound represented by formula (1), which is obtained by chirally resolving the racemic mixture containing the compound represented by formula (1) following by the rotary-evaporation to dryness. The obtained compound is in the amorphous form.
The compound of formula (1) has two chiral centers. In order to obtain a single isomer, those skilled in the art will resolve the racemic mixture. According to WO2012022121, the racemic mixture containing the compound represented by formula (1) is firstly obtained, and then resolved to obtain the compound represented by formula (1), which makes it difficult to produce the compound represented by formula (1) in a GMP standard plant, resulting in the difficulty in the industrialization and the higher production cost.